Enabling Secure Connections in iPhone/iPad

To Enable Incoming Email (POP/IMAP) SSL

• From the Home screen, tap Settings.

• Tap Accounts & passwords (Or Mail, Contacts, Calendars on older devices) and choose the desired email account.
• Tap your account name again if needed
• Scroll down and tap Advanced.
• From the Incoming Settings menu, slide Use SSL to ON.
• Make sure the Hostname ends in his.com. It should look like: mail.his.com, psaXXX.his.com, zimbraXXX.his.com, zmailX.his.com.
• Authentication = Password
• Tap Server Port and make the following change:
  For IMAP - 993
  For POP - 995
• Tap Account at the top to go back

To Enable Outgoing Email SSL

• From the SMTP menu, tap the primary outgoing server for the account. This will be the server name assigned to your domain.
• Make sure the Hostname ends in his.com. It should look like: mail.his.com, psaXXX.his.com, zimbraXXX.his.com, zmailX.his.com.
• Next to Use SSL, tap ON.
• Tap Server Port and change the port to 587. Wait until the phone verifies it. You can also use port 465
• Make sure Authentication is enabled and set to "Password"
• Tap Account at the top to go back.
• Tap Done

You may need to restart your iPhone for the changes to take effect.